1. Field
The following description relates to a semiconductor package, and to, for example, a semiconductor package in which a driving circuit, a low-side output power device and a high-side output power device are included in a monolithic type semiconductor die.
2. Description of Related Art
In recent years, demands on portable products have rapidly increased in the electronic product market. To meet the demand of making electronic products portable, parts that are used in portable systems have to be inevitably reduced in size, weight and thickness.
To produce parts that are minimized in size, weight and thickness, various technologies for size reduction of individual mounted parts are utilized. These technologies include system on chip (SOC) technology for making a plurality of individual devices into one chip, system in package (SIP) technology for integrating a plurality of individual devices into one package, and other similar technologies.
In recent years, with the trends of versatility of functions and miniaturization of mobile communication terminals, various parts embedded in terminals or modules embedded in a handset apparatus related thereto have been minimized in size. Mobile communication terminals include, for example, portable phones, personal digital assistants (PDAs), smart phones and other various terminals for media, such as MP3 players. Miniaturization technology also applies to other computing products such as tablet computers and new generation small-form-factor notebook computers referred to as UltraBooks. For miniaturization of the modules, studies on implementing parts of passive devices, active devices, and integrated circuit (IC) chips in one package have been attempted.
As a result, the number of module products is increasing, and various kinds of packages have been developed and released to support the growing demand of miniaturized modules. For example, companies have developed various package technologies that simultaneously improve an output power density of a semiconductor device and reduce production cost.
With this effort, 3D stacking technology for three-dimensionally coupling semiconductor dies has been developed, and semiconductor packages integrated as compared with the related art have been developed. However, since a driving circuit, a low-side output power device, and a high-side output power device are configured in separate semiconductor dies from each other, there are limitations on the integration of semiconductor packages.
The standard die is attached to a copper pad that is exposed at the bottom of the package. The pad is not a power electrode that carries high current. It is simply a thermal electrode. There is no backmetal on the back-side of standard monolithic buck converters. There is no electrical current flowing. The power ground is connected to separate pins on the periphery of the QFN package, and not connected to the bottom of the semiconductor die or the exposed pad (see Korean Laid-open Patent No. 10-2011-0074570 and US Laid-open patent No. 2013-0043940).